Systems for producing an image of a physical object are widespread in several technical fields. One area of particular commercial interest is in the field of CT C-arm systems i.e. C-arm systems which are capable of CT-like 3D imaging. Good 3D image quality requires a C-arm rotation range of at least 180° plus fan angle.
In some medical or other cases it may be desirable to reduce the rotation range of the C-arm. One reason could be that the examination process is faster and therefore more economically. Also, a lower number of examined CT slices due to the reduced rotation range of the object causes less influences of X-rays to the object. Further, most C-arm systems have a limited angular range itself.
However, the image reconstruction of a CT-data volume of CT slices with an angular range of much less than 180° plus fan angle may cause an unacceptable level of strong artefacts due to the fact of strong density variations on material boundaries of the examined object of interest. More precisely, the reconstructed image may show artificial streaks or gradients.